Leadership is a very old concept which has been discussed over hundreds of centuries. However, especially after the industrialization in the late 1700’s, contemporary administration had been adopted to the economic system. With this adaptation, many thinkers had studied over leadership. After these studies, they have created some useful theories that can be used in the recent work life. In this section we will focus on most famous theories. These are summarized in the following:
· XY theory of Douglas Mc Gregor
· System Four approach of Rennis Likert
· Immaturity / maturity theory.
For the last one, Immaturity / maturity theory, Arygis analyzed the individual behavior instead of the group behavior. He had observed the individual development by the help of the leaders. In his study he stated that:
· Individuals move from a passive state to a state of increasing activity.
· Individuals develop from a state of dependency upon others to a state of relative independence.
· Individuals behave in only a few ways, but after growing they are capable of behaving in many ways.
· Individuals have erratic, casual, and shallow interests but they develop to demand deeper and stronger interests.
· The time perspective is very short, involving only the present, but as they mature, their time perspective increases to include the past and the future.
· Individuals are subordinate to everyone, but they move to equal or superior positions with others.
· Seventh, individuals lack an awareness of a but they are not only aware of, but they are able to control
During the above mentioned process the leaders take an important part in the development of the subordinates. They give empowerment to the subordinates in order to make them decide for the future of the company. This kind of a leadership also allows the company to train its middle and top managers.
 Tuğray Kaynak, Organizasyonel Davranış, First Ed., İstanbul:
, 1990, p. 25. İstanbul
 Osama Solieman, “Immaturity Maturity Model”, http://ai.arizona.edu/hchen/class_presentation/2005MIS580/5